Field of the Invention
The disclosure is related to the in-cell touch liquid crystal panel technology field, and more particular to a method and a device for decreasing a leakage current of an in-cell touch liquid crystal panel.
Discussion of the Related Art
The liquid crystal display equipped with the touch panel touch is a portable flat panel display widely usedcurrently, which has been gradually become a display with high-resolution color display screen widely used by a variety of electronic devices (e.g., a mobile communication terminal, a personal digital assistant (PDA), a digital camera, a computer, a notebook computer, etc.). In recent years, the original external touch panel member and the liquid crystal panel are manufactured integrally (in-cell touch), thereby achieving thinness and lightweight of the panel, and the manufacturing cost is saved due to the touch sensor embedded in the pixel.
Currently, the general in-cell touch liquid crystal displays is usually composed of a upper substrate, a lower substrate and an intermediate liquid crystal layer, and the substrate is composed of a glass, a electrodes and etc. If both of the upper substrate and the lower substrate have electrodes, which may form a display with the vertical electric field mode, such as TN (twist nematic) mode, VA (vertical alignment) mode, and MVA (Multidomain Vertical Alignment) mode developed for solving a narrow viewing angle. Another type display is different from the above display, in which the electrode is only located on one side of the substrate to form a display with the transverse electric field mode, such as IPS (In-plane switching) mode, FFS (Fringe Field Switching) and etc. Since the structure of the in-cell touch liquid crystal panel, the electrodes thereof often commonly use one electrode of the vertical electric field or the transverse electric field, i.e. the common electrode, and its operating principle is: when scanning a touch signal, a signal originally inputted to the common electrode for the display is transformed into a signal for scanning the touch signal, after scanning the touch signal is end, the signal is then transferred into a signal for the display.
FIG. 1 is a schematic view of a pixel array of an in-cell touch liquid crystal panel. As shown in FIG. 1, D1-D5 indicate data lines, G1-G5 indicate scan lines. FIG. 2 is a schematic view of a pixel circuit. As shown in FIG. 2, the pixel circuit includes: a thin film transistor, a liquid crystal capacitor (Clc), a storage capacitor (Cst), a parasitic capacitor (Cgs) between a gate and a source of the thin film transistor, a pixel electrode (pixel ITO), a common electrode on a side of a color filter layer and a common electrode on a side of an array layer. Since in the panel with the transverse electric field mode, there is no common electrode on the side of the color filter layer, and there is only the common electrode on the side of the array layer. Therefore, the liquid crystal capacitor and the storage capacitor are connected to the common electrode of the side of the array layer.
In the existing in-cell touch liquid crystal panel, a larger leakage current still exists and results in increase of the power consumption and low frame quality.